A Novel Implantable Piezoresistive Microsensor for Intraocular Pressure Measurement.

Area of Science:

• Biomedical Engineering
• Ophthalmology
• Microfluidics

Background:

• Glaucoma is a leading cause of irreversible blindness worldwide.
• Elevated intraocular pressure (IOP) is a major risk factor for glaucoma.
• Current IOP measurement devices lack continuous monitoring capabilities.

Purpose of the Study:

• To develop an implantable piezoresistive sensor for continuous intraocular pressure (IOP) monitoring.
• To address the need for long-term IOP tracking in glaucoma patients.

Main Methods:

• Fabrication of an implantable piezoresistive IOP sensor utilizing microfluidic technology.
• Calibration and testing of the sensor for sensitivity, linearity, stability, and repeatability.
• In vivo implantation in rabbit vitreous to detect IOP fluctuations.

Main Results:

• The sensor demonstrated a sensitivity of 0.00257 Ω/mbar with excellent linearity, stability, and repeatability.
• The average measurement error was ±0.5 mbar.
• Successful detection of IOP fluctuations after implantation in a rabbit model.

Conclusions:

• The developed microfluidic-based IOP sensor is simple, easy to fabricate, and suitable for long-term continuous monitoring.
• Presents a novel approach for IOP sensing and a new method for daily glaucoma patient care.